Adjustable dental impression tray

ABSTRACT

The disclosure is that of an invention directed to an adjustable dental impression tray including a primary unit and a complementary movable unit slidably mounted telescopically on the primary unit for proximal and distal adjustment with respect thereto. The primary unit is provided with a T-slot disposed in registry with a complementary slot in the movable unit and a securing device engagable through both slots is provided to secure the movable unit in a predetermined adjusted position with respect to the primary unit; and a retainer is provided to prevent accidental disassembly of the securing device.

United States Patent 1191 Burns June 24, 1975 ADJUSTABLE DENTAL IMPRESSION TRAY [76] Inventor: William F. Burns, 21 Brooklawn,

Pompton Plains, NJ. 07444 [22] Filed: Apr. 18, 1974 [21] Appl. No.: 461,885

[52] US. Cl. 32/17 [51] Int. Cl. A61c 9/00 [58] Field of Search 32/ 17 [56 References Cited UNITED STATES PATENTS 1,725,830 8/1929 Ryerson 32/17 1,891,649 12/1932 Meurer 32/17 Primary Examiner-Robert Peshock Attorney, Agent, or Firm-Thomas E. Tate [5 7] ABSTRACT The disclosure is that of an invention directed to an adjustable dental impression tray including a primary unit and a complementary movable unit slidably mounted telescopically on the primary unit for proximal and distal adjustment with respect thereto. The primary unit is provided with a T-slot disposed in registry with a complementary slot in the movable unit and a securing device engagable through both slots is provided to secure the movable unit in a predetermined adjusted position with respect to the primary unit; and a retainer is provided to prevent accidental disassembly of the securing device.

2 Claims, 9 Drawing Figures PATENTEDJUN 24 m5 SHEET villi/111'! I ADJUSTABLE DENTAL IMPRESSION TRAY Thisinvention relates generally to new and useful improvements in'dental impression trays and particularly seeks to provide a novel dental impression tray in which adjustments thereof in-proximal and distal directions readily may be effected.

Adjustable dental trays, in general, have been known for many years,-'of which the following show typical examples: Pat. Nos. 753,679 of Mar". 1, 1904; 755,670 of Mar. 29, 1904; 765919 of July 26, 1904;

1,054,999 of Mar. 4, 1913; 1,493,417 of May 6 1924; 2,426,388 of Aiig. 26, 1947; Swiss Patent No. 57,395 of July 21, 1911 and German PatQNo. 1,083,017 of June 9, 1960. Y I 1 However, none of these provide the simplicity of construction and the rigidity; control and locking of the relatively adjustable parts as effected by the inventive construction disclosed herein and it is believed that none of them has achieved commercial acceptance.

Therefore, an object of this invention is to provide an adjustable dental impression tray that includes a primary proximal unit anda complementary movable distal unit slidably mounted on the primary unit for proximal and distal adjustment; with respect thereto.

Anotherobject of this invention is to provide an impression tray of the character stated in which the primary unit is'provided with a T- slot disposed in registry with a'con plementary'slot in the movable unit and in which a locking device engag able through both slots is provided to secure the movable unit in a predetermined adjusted position with respect to the primary unit.

A further object of this invention is to provide an impression tray of the character stated that is simple in design, rugged in construction and economical to manufacture.

With these and other objects, the nature of which will become apparent, the nature of the invention will be more fully understood by reference to the drawings, the accompanying detailed description and the appended claims.

IN THE DRAWINGS FIG. 1 is an exploded isometric view of an adjustable tray constructed in accordance with this invention for use in taking upper dental impressions;

FIG. 2 is an isometric view similar to FIG. 1 but showing the tray in its assembled condition with the adjustable unit in its proximally retracted position;

FIG. 3 is an enlarged longitudinal vertical section taken along line 33 of FIG. 2;

FIG. 4 is an enlarged transverse vertical section taken along line 44 of FIG. 2;

FIG. 5 is a fragmentary longitudinal section similar to FIG. 3 but showing the adjustable unit in a distally extended position;

FIG. 6 an exploded isometric view of an adjustable tray constructed in accordance with this invention for use in taking lower dental impressions;

FIG. 7 is an isometric view similar to FIG. 6 but showing the tray in its assembled condition with the adjustable units partly distally extended;

FIG. 8 is a transverse vertical section taken along line 88 of FIG. 7; and

FIG. 9 is a fragmentary longitudinal section taken along line 99 of FIG. 8.

Referring to the drawings in detail one form of the invention, as illustrated, is embodied in an adjustable dental impression tray including a primary unit or tray generally indicated 10 (see FIGS. 1-5) having adistally open generally U-shaped occlusal bottom 11, a raised centrally disposed palatal portion 12 and an upstanding facial wall or skirt 13 around the outer periphery of the occlusal bottom 11. I

The palatal po'rtion12is provided with an elongated axially oriented T sot open at its distal end and having a medianly disposed crossbar 14 and a downwardly opening stem 15, tius leaving the upper surface of the Adjustability of the effective length of the'primary tray 10 is provided by a complementary extension unit generally indicated 16 which is slidably mounted on the primary tray for movement in proximal and distal directions with respect thereto and includes a pair of spaced parallel occlusal bottom portions 17, 17 underlying the bottom 11, a central palatal portion 18 underlying the palatal portion 12, and a pair of facial walls 19,19 disposed outwardly of the wall 13 and terminating in top channels 20, 20 engaged over the top of the wall 13.

A longitudinal slot 21 is provided intermediate the proximal and distal ends of the palatal portion 18 in registry with the stem 15 of the T-slot in the palatal portion 12 so that the two slots together may accomodate means generallyindicated 22 for securing the extension unit 16 in any desired position on the primary unit 10 as will be hereinafter more fully described.

The securing or locking means 22 comprises a threaded stem or bolt 23 having a diameter to fit freely through the slots 15 and 21 and provided with a rectangular upper head 24 for slidable reception within the cross slot 14, a knurled clamp nut 25 located beneath the palatal portion 18 and a lower nut restraining head 26 which is rigidly affixed to the lower end of the bolt 23 after the nut 25 has become threadably engaged therewith. The lower head 26 prevents the nut 25 from disengagement with the bolt, thus avoiding any possibility of the nut dropping off into the mouth or throat of a patient during the taking of a dental impression.

Adjustment of the extension unit 16 relative to the primary unit 10 is readily effected simply by backing off the nut 25, sliding the extension in either a proximal or distal direction to its desired position and then retightening the nut. Since the shape of the extension unit 16 is complementary to that of the primary unit 10, angular or other distortions of relative positions between the two units cannot occur when relative sliding movements for adjustment purposes take place.

After each use the complete unit may be properly cleaned by disengaging the extension unit 16 and its securing means 22 from the primary unit 10 and autoclaving or otherwise cleaning the thus separated parts.

A proximally extending handle 27, preferably formed as an integral extension of the facial wall 13, is used to manipulate the assembled impression tray when in use.

As shown in FIGS. 6-9 of the drawings, the principles of this invention are equally applicable to trays that are to be used for the taking of lower dental impressions.

In this embodiment a primary unit generally indicated 28 is of a distally open generally U-shaped plan configuration and includes two legs 29,29 connected by a common occlusal bottom wall 30. The distal end portion of each leg 29 is provided with a T-slot 31 for registry with a corresponding slot 32 formed in a complementary slide extension unit 33 adapted to be secured in any desired adjusted position by means 34 indentical with the previously described securing means 32. A proximally extending manipulating handle 35 also is provided.

In both of the above described embodiments of the invention the relative lengths and dispositions of the T- slots and the associated slots in the extension units providean unusual degree of operational flexibility to the user because it is possible to insert the assembled tray into a patients mouth with the extension units proximally retracted and with the securing means 22 or 34 located at a convenient position at or between the proximal and distal extremities of movement; and thereafter any desired distal adjustment of the extension unit may be effected in situ to achieve the proper total tray length and secured in such adjusted position.

It will be understood that although the above described embodiments of the invention are directed to trays for taking full arch dental impressions, the principles of the invention are equally adaptable for trays to be used for the taking of quadrant, anterior, edentulous or pediatric impressions. Also, the materials of construction may be such as those currently acceptable for conventional trays, including corrosion resistant metals and inert rigid plastics or metals coated with inert plastics such as halogenated hydrocarbons.

It is of course to be understood that variations in arrangements and proportions of parts may be made within the scope of the appended claims.

I claim:

1. An adjustable dental impression tray including a primary impression unit. an extension unit telescopically mounted on said primary unit for adjustment relative thereto in proximal and distal directions, and releasable means for securing said primary and said extension units in their adjusted position; said primary unit being provided with an elongated longitudinally extending securing means retaining slot of T-shaped cross-section in open communication with the distal end and with one face thereof, said extension unit being provided with an elongated slot in juxtaposition to the said T-slot of said primary unit and in communication therewith; said securing means comprising a mounting head slidably retained within the T-slot of said primary unit, a threaded stem affixed to said head and extending through and beyond both of said elongated slots, a clamp nut threadably engaged with the extending portion of said stem, and a retainer head affixed to the projecting end of said stem for preventing disassembly of said securing means.

2. The adjustable dental impression tray of claim 1 in which said primary unit includes a portion having a bottom containing said T-slot and a pair of spaced parallel side walls extending upwardly beyond the general plane of said bottom; and in which said telescopic extension unit has a cross-section complementary to that of the side wall containing portion of said primary unit and includes a bottom in juxtaposition to that of said primary unit and containing said juxtaposed elongated slot. 

1. An adjustable dental impression tray including a primary impression unit, an extension unit telescopically mounted on said primary unit for adjustment relative thereto in proximal and distal directions, and releasable means for securing said primary and said extension units in their adjusted position; said primary unit being provided with an elongated longitudinally extending securing means retaining slot of T-shaped cross-section in open communication with the distal end and with one face thereof, said extension unit being provided with an elongated slot in juxtaposition to the said T-slot of said primary unit and in communication therewith; said securing means comprising a mounting head slidably retained within the T-slot of said primary unit, a threaded stem affixed to said head and extending through and beyond both of said elongated slots, a clamp nut threadably engaged with the extending portion of said stem, and a retainer head affixed to the projecting end of said stem for preventing disassembly of said securing means.
 2. The adjustable dental impression tray of claim 1 in which said primary unit includes a portion having a bottom containing said T-slot and a pair of spaced parallel side walls extending upwardly beyond the general plane of said bottom; and in which said telescopic extension unit has a cross-section complementary to that of the side wall containing portion of said primary unit and includes a bottom in juxtaposition to that of said primary unit and containing said juxtaposed elongated slot. 